10kW Solar System Cost: $9,810 to $11,700 after STCs, by Capital, with Battery and Three-Phase Checks (October 2026)

What a 10 kW solar system costs in October 2026

The national standard offer for a 10 kW system is $9,810 and the premium offer is $11,700 in October 2026, installed, after the STC discount at $39 per certificate and including GST. That is 0.98 to 1.17 dollars per watt. 10 kW is a published size in the installer-offer index behind our price data, so neither figure is interpolated. Among the capitals Perth is cheapest at $8,240 and Darwin dearest at $14,930 on the standard offer.

These are offers submitted by installers, not quotes received by households, and no sample size is published for them. Our own quotes series starts printing a median and a count for each city once ten checked quotes exist; until then the index is the benchmark and the quote check measures a quote against it.

The step up from 6.6 kW costs $3,036 more on the national standard offer, and the dollars per watt fall from 1.03 at 6.6 kW to 0.98 at 10 kW because the inverter, the crew day and the connection paperwork are spread over 23 panels instead of 15.

10 kW price by capital city, standard and premium

Sydney is $8,780 to $10,490, Melbourne $8,920 to $10,410, Brisbane $9,460 to $11,210 and Perth $8,240 to $9,880. The premium column is the index's higher-specification offer (European or premium-brand panels and inverters, as the index defines it); the gap between the two columns is $1,890 nationally and is mostly the inverter and panel brand, not the labour.

Each city link opens the 10 kW page for that capital with its own output, network rules and payback. Regional cities use the nearest indexed capital and say so; all 20 city pages are listed at the foot of this page.

STC audit for 10 kW: Zones 1, 3 and 4

A 10 kW system earns 69 certificates in Zone 3, worth $2,691 at $39 each; 59 in Zone 4, worth $2,301; and 81 in Zone 1, worth $3,159. The count is kilowatts times the zone factor times 5 deeming years, rounded down to the whole certificate. The installer creates the certificates and the quote should show the count and the price per certificate as its own deduction line.

Two checks. First, a certificate line more than 10 per cent under the value for your zone means the installer has priced the STCs below the market and is recovering the gap in the hardware or labour lines. Second, the deeming period drops to 4 years on 1 January 2027, so a Zone 3 install that slips into January earns 55 certificates, $546 less; the quote should say who carries that.

When a 10 kW system needs three phase

Under the 133 per cent design rule a 10 kW array needs an inverter of at least 7.52 kW. Whether that inverter can connect on single phase depends on the distributor, not on a national rule. Of the eight capitals, 5 distributors publish a single-phase inverter cap on pages we could read (Ausgrid 30 kVA, Western Power 30 kVA, SA Power Networks 10 kVA, Evoenergy 10 kVA, TasNetworks 10 kVA), and 2 more carry a cap in our data from an industry summary because their sites blocked us (Energex 10 kVA, Power and Water 10 kVA). Every one of those caps is at or above 7.52 kW, so on the figures we hold a 10 kW array does not force three phase in Sydney, Brisbane, Perth, Adelaide, Canberra, Hobart or Darwin; the 5 kVA habit many installers quote is a norm, not the network's limit.

What three phase changes at 10 kW is the export, not the inverter. Single-phase export is capped at 5 kW by most distributors that publish a figure and at 1.5 kW by SA Power Networks, so a 10 kW array on single phase sells less of its midday output. A three-phase home connects a three-phase inverter, adds $375 to $1,500 on the sourced range, and spreads the output across three phases. The three-phase cost page carries the caps for every distributor and the phase upgrade cost.

Export limiting: what a 5 kW cap takes from 10 kW

An export limiter is a meter and an inverter setting that holds export at the agreed figure; it costs $200 to $500 installed on the sourced range and is how a 10 kW inverter connects on single phase without a network study. The question is how much output it wastes. We model each capital's average day as a half-sine curve over 10 hours, cap it at 5 kW with no daytime load, and sum the energy above the cap month by month. In Sydney that is 1,960 kWh a year, 13.8 per cent of output, worth $78 at the New South Wales feed-in rate; in Perth it is 3,386 kWh, worth $93.

Those are upper bounds: any daytime load under the cap is used, not clipped, and cloudy days clip nothing. The window and the curve are modelling assumptions written in the page derivations. Flexible export, where the distributor offers it, lifts the cap when the local network has room and reduces the figure further.

EV, pool and heat pump loads: what 10 kW is for

Ten kilowatts earns its price when the output is used at home instead of exported. Three loads do that in daylight. An electric car driven 12,000 km a year at 15 kWh per 100 km uses about 1,800 kWh; a 1 kW pool pump run 6 hours a day for 180 days uses 1,080 kWh; a heat pump water heater at 3 kWh a day uses 1,095 kWh. All three are our assumptions, written in the page source, and together they are 3,975 kWh a year.

In Sydney a 10 kW array makes about 14,240 kWh a year. At our baseline of 35 per cent self-consumption the home uses 4,984 kWh of that; add the three loads in daylight and it uses 8,959 kWh, 63 per cent of output. The saving moves from $2,065 to $3,257 a year at 34 cents grid power and 4 cents feed-in, and the standard-offer payback shortens from 4.3 years to 2.7.

A household without those loads, using under about 15 kWh a day, exports most of a 10 kW array and should price 6.6 kW first; the 6.6 kW page has the same tables at that size.

Lifetime cost per kWh of 10 kW by capital

Divide the installed price by 25 years of output at 0.5 per cent a year degradation and the standard offer costs 2.2 cents per kWh in Perth, 2.6 cents in Sydney, 2.9 cents in Melbourne and 3.8 cents in Hobart, against grid rates of 33 to 40 cents across the states. Darwin pays the highest price and has the equal-highest yield, and the yield does not rescue it: at 3.9 cents it is the dearest kWh in the table, a tenth of a cent above Hobart.

The figure is what each kWh costs you to make; it only becomes a saving when that kWh displaces grid power at the rate in the last column rather than earning the feed-in rate. The cost per watt page does the same calculation for 6.6 kW.

10 kW with a 10 or 14 kWh battery

A 10 kWh battery is listed at $9,500 to $12,500 installed before the federal discount and a 13.5 kWh unit at $12,000 to $15,000. The Cheaper Home Batteries Program pays 6.8 certificates per usable kWh on the first 14 kWh: 68 certificates and $2,652 on 10 kWh, 91 and $3,549 on 13.5 kWh, and 95 and $3,705 on a full 14 kWh, all at $39 per STC for installs to 31 December 2026. Add the national standard 10 kW offer and a 10 kW system with a 10 kWh battery is $16,658 to $19,658; with 13.5 kWh it is $18,261 to $21,261.

A 10 kW array leaves plenty to charge with. At 35 per cent daytime use the average-day surplus is 25.4 kWh in Sydney, 23.4 kWh in Melbourne and 28.6 kWh in Perth, so a 10 or 13.5 kWh battery fills on an average day in every capital. The battery's own payback depends on the gap between the grid rate and the feed-in rate in your state; the battery guide works it. The factor steps down to 5.7 certificates per kWh on 1 January 2027.

Panels, roof and output

At 440 W a 10 kW array is 23 panels, 10.12 kW of panels, and about 46 square metres of roof at two square metres a panel, which usually means two roof faces. Output runs from 12,780 kWh a year in Hobart to 16,060 kWh in Perth, from each capital's Bureau of Meteorology exposure and the Clean Energy Council yield figure for that city.

10 kW solar by city

Each page below carries the 10 kW price for that city, its STC count, its network's connection limits, monthly output and payback; the national summary is on the 10 kW size page, and the Sydney and Melbourne city pages hold every size side by side. For the whole price picture start at solar panel costs.

10 kW solar system questions